syscall: validate ParseDirent inputs

[gostls13.git] / src / syscall / syscall_darwin.go

// Copyright 2009,2010 The Go Authors. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.

// Darwin system calls.
// This file is compiled as ordinary Go code,
// but it is also input to mksyscall,
// which parses the //sys lines and generates system call stubs.
// Note that sometimes we use a lowercase //sys name and wrap
// it in our own nicer implementation, either here or in
// syscall_bsd.go or syscall_unix.go.

package syscall

import (
        errorspkg "errors"
        "unsafe"
)

const ImplementsGetwd = true

func Getwd() (string, error) {
        buf := make([]byte, 2048)
        attrs, err := getAttrList(".", attrList{CommonAttr: attrCmnFullpath}, buf, 0)
        if err == nil && len(attrs) == 1 && len(attrs[0]) >= 2 {
                wd := string(attrs[0])
                // Sanity check that it's an absolute path and ends
                // in a null byte, which we then strip.
                if wd[0] == '/' && wd[len(wd)-1] == 0 {
                        return wd[:len(wd)-1], nil
                }
        }
        // If pkg/os/getwd.go gets ENOTSUP, it will fall back to the
        // slow algorithm.
        return "", ENOTSUP
}

type SockaddrDatalink struct {
        Len    uint8
        Family uint8
        Index  uint16
        Type   uint8
        Nlen   uint8
        Alen   uint8
        Slen   uint8
        Data   [12]int8
        raw    RawSockaddrDatalink
}

// Translate "kern.hostname" to []_C_int{0,1,2,3}.
func nametomib(name string) (mib []_C_int, err error) {
        const siz = unsafe.Sizeof(mib[0])

        // NOTE(rsc): It seems strange to set the buffer to have
        // size CTL_MAXNAME+2 but use only CTL_MAXNAME
        // as the size. I don't know why the +2 is here, but the
        // kernel uses +2 for its own implementation of this function.
        // I am scared that if we don't include the +2 here, the kernel
        // will silently write 2 words farther than we specify
        // and we'll get memory corruption.
        var buf [CTL_MAXNAME + 2]_C_int
        n := uintptr(CTL_MAXNAME) * siz

        p := (*byte)(unsafe.Pointer(&buf[0]))
        bytes, err := ByteSliceFromString(name)
        if err != nil {
                return nil, err
        }

        // Magic sysctl: "setting" 0.3 to a string name
        // lets you read back the array of integers form.
        if err = sysctl([]_C_int{0, 3}, p, &n, &bytes[0], uintptr(len(name))); err != nil {
                return nil, err
        }
        return buf[0 : n/siz], nil
}

func direntIno(buf []byte) (uint64, bool) {
        return readInt(buf, unsafe.Offsetof(Dirent{}.Ino), unsafe.Sizeof(Dirent{}.Ino))
}

func direntReclen(buf []byte) (uint64, bool) {
        return readInt(buf, unsafe.Offsetof(Dirent{}.Reclen), unsafe.Sizeof(Dirent{}.Reclen))
}

func direntNamlen(buf []byte) (uint64, bool) {
        return readInt(buf, unsafe.Offsetof(Dirent{}.Namlen), unsafe.Sizeof(Dirent{}.Namlen))
}

//sys   ptrace(request int, pid int, addr uintptr, data uintptr) (err error)
func PtraceAttach(pid int) (err error) { return ptrace(PT_ATTACH, pid, 0, 0) }
func PtraceDetach(pid int) (err error) { return ptrace(PT_DETACH, pid, 0, 0) }

const (
        attrBitMapCount = 5
        attrCmnFullpath = 0x08000000
)

type attrList struct {
        bitmapCount uint16
        _           uint16
        CommonAttr  uint32
        VolAttr     uint32
        DirAttr     uint32
        FileAttr    uint32
        Forkattr    uint32
}

func getAttrList(path string, attrList attrList, attrBuf []byte, options uint) (attrs [][]byte, err error) {
        if len(attrBuf) < 4 {
                return nil, errorspkg.New("attrBuf too small")
        }
        attrList.bitmapCount = attrBitMapCount

        var _p0 *byte
        _p0, err = BytePtrFromString(path)
        if err != nil {
                return nil, err
        }

        _, _, e1 := Syscall6(
                SYS_GETATTRLIST,
                uintptr(unsafe.Pointer(_p0)),
                uintptr(unsafe.Pointer(&attrList)),
                uintptr(unsafe.Pointer(&attrBuf[0])),
                uintptr(len(attrBuf)),
                uintptr(options),
                0,
        )
        use(unsafe.Pointer(_p0))
        if e1 != 0 {
                return nil, e1
        }
        size := *(*uint32)(unsafe.Pointer(&attrBuf[0]))

        // dat is the section of attrBuf that contains valid data,
        // without the 4 byte length header. All attribute offsets
        // are relative to dat.
        dat := attrBuf
        if int(size) < len(attrBuf) {
                dat = dat[:size]
        }
        dat = dat[4:] // remove length prefix

        for i := uint32(0); int(i) < len(dat); {
                header := dat[i:]
                if len(header) < 8 {
                        return attrs, errorspkg.New("truncated attribute header")
                }
                datOff := *(*int32)(unsafe.Pointer(&header[0]))
                attrLen := *(*uint32)(unsafe.Pointer(&header[4]))
                if datOff < 0 || uint32(datOff)+attrLen > uint32(len(dat)) {
                        return attrs, errorspkg.New("truncated results; attrBuf too small")
                }
                end := uint32(datOff) + attrLen
                attrs = append(attrs, dat[datOff:end])
                i = end
                if r := i % 4; r != 0 {
                        i += (4 - r)
                }
        }
        return
}

//sysnb pipe() (r int, w int, err error)

func Pipe(p []int) (err error) {
        if len(p) != 2 {
                return EINVAL
        }
        p[0], p[1], err = pipe()
        return
}

func Getfsstat(buf []Statfs_t, flags int) (n int, err error) {
        var _p0 unsafe.Pointer
        var bufsize uintptr
        if len(buf) > 0 {
                _p0 = unsafe.Pointer(&buf[0])
                bufsize = unsafe.Sizeof(Statfs_t{}) * uintptr(len(buf))
        }
        r0, _, e1 := Syscall(SYS_GETFSSTAT64, uintptr(_p0), bufsize, uintptr(flags))
        use(unsafe.Pointer(_p0))
        n = int(r0)
        if e1 != 0 {
                err = e1
        }
        return
}

/*
 * Wrapped
 */

//sys   kill(pid int, signum int, posix int) (err error)

func Kill(pid int, signum Signal) (err error) { return kill(pid, int(signum), 1) }

/*
 * Exposed directly
 */
//sys   Access(path string, mode uint32) (err error)
//sys   Adjtime(delta *Timeval, olddelta *Timeval) (err error)
//sys   Chdir(path string) (err error)
//sys   Chflags(path string, flags int) (err error)
//sys   Chmod(path string, mode uint32) (err error)
//sys   Chown(path string, uid int, gid int) (err error)
//sys   Chroot(path string) (err error)
//sys   Close(fd int) (err error)
//sys   Dup(fd int) (nfd int, err error)
//sys   Dup2(from int, to int) (err error)
//sys   Exchangedata(path1 string, path2 string, options int) (err error)
//sys   Exit(code int)
//sys   Fchdir(fd int) (err error)
//sys   Fchflags(fd int, flags int) (err error)
//sys   Fchmod(fd int, mode uint32) (err error)
//sys   Fchown(fd int, uid int, gid int) (err error)
//sys   Flock(fd int, how int) (err error)
//sys   Fpathconf(fd int, name int) (val int, err error)
//sys   Fstat(fd int, stat *Stat_t) (err error) = SYS_FSTAT64
//sys   Fstatfs(fd int, stat *Statfs_t) (err error) = SYS_FSTATFS64
//sys   Fsync(fd int) (err error)
//sys   Ftruncate(fd int, length int64) (err error)
//sys   Getdirentries(fd int, buf []byte, basep *uintptr) (n int, err error) = SYS_GETDIRENTRIES64
//sys   Getdtablesize() (size int)
//sysnb Getegid() (egid int)
//sysnb Geteuid() (uid int)
//sysnb Getgid() (gid int)
//sysnb Getpgid(pid int) (pgid int, err error)
//sysnb Getpgrp() (pgrp int)
//sysnb Getpid() (pid int)
//sysnb Getppid() (ppid int)
//sys   Getpriority(which int, who int) (prio int, err error)
//sysnb Getrlimit(which int, lim *Rlimit) (err error)
//sysnb Getrusage(who int, rusage *Rusage) (err error)
//sysnb Getsid(pid int) (sid int, err error)
//sysnb Getuid() (uid int)
//sysnb Issetugid() (tainted bool)
//sys   Kqueue() (fd int, err error)
//sys   Lchown(path string, uid int, gid int) (err error)
//sys   Link(path string, link string) (err error)
//sys   Listen(s int, backlog int) (err error)
//sys   Lstat(path string, stat *Stat_t) (err error) = SYS_LSTAT64
//sys   Mkdir(path string, mode uint32) (err error)
//sys   Mkfifo(path string, mode uint32) (err error)
//sys   Mknod(path string, mode uint32, dev int) (err error)
//sys   Mlock(b []byte) (err error)
//sys   Mlockall(flags int) (err error)
//sys   Mprotect(b []byte, prot int) (err error)
//sys   Munlock(b []byte) (err error)
//sys   Munlockall() (err error)
//sys   Open(path string, mode int, perm uint32) (fd int, err error)
//sys   Pathconf(path string, name int) (val int, err error)
//sys   Pread(fd int, p []byte, offset int64) (n int, err error)
//sys   Pwrite(fd int, p []byte, offset int64) (n int, err error)
//sys   read(fd int, p []byte) (n int, err error)
//sys   Readlink(path string, buf []byte) (n int, err error)
//sys   Rename(from string, to string) (err error)
//sys   Revoke(path string) (err error)
//sys   Rmdir(path string) (err error)
//sys   Seek(fd int, offset int64, whence int) (newoffset int64, err error) = SYS_LSEEK
//sys   Select(n int, r *FdSet, w *FdSet, e *FdSet, timeout *Timeval) (err error)
//sys   Setegid(egid int) (err error)
//sysnb Seteuid(euid int) (err error)
//sysnb Setgid(gid int) (err error)
//sys   Setlogin(name string) (err error)
//sysnb Setpgid(pid int, pgid int) (err error)
//sys   Setpriority(which int, who int, prio int) (err error)
//sys   Setprivexec(flag int) (err error)
//sysnb Setregid(rgid int, egid int) (err error)
//sysnb Setreuid(ruid int, euid int) (err error)
//sysnb Setrlimit(which int, lim *Rlimit) (err error)
//sysnb Setsid() (pid int, err error)
//sysnb Settimeofday(tp *Timeval) (err error)
//sysnb Setuid(uid int) (err error)
//sys   Stat(path string, stat *Stat_t) (err error) = SYS_STAT64
//sys   Statfs(path string, stat *Statfs_t) (err error) = SYS_STATFS64
//sys   Symlink(path string, link string) (err error)
//sys   Sync() (err error)
//sys   Truncate(path string, length int64) (err error)
//sys   Umask(newmask int) (oldmask int)
//sys   Undelete(path string) (err error)
//sys   Unlink(path string) (err error)
//sys   Unmount(path string, flags int) (err error)
//sys   write(fd int, p []byte) (n int, err error)
//sys   mmap(addr uintptr, length uintptr, prot int, flag int, fd int, pos int64) (ret uintptr, err error)
//sys   munmap(addr uintptr, length uintptr) (err error)
//sys   readlen(fd int, buf *byte, nbuf int) (n int, err error) = SYS_READ
//sys   writelen(fd int, buf *byte, nbuf int) (n int, err error) = SYS_WRITE

/*
 * Unimplemented
 */
// Profil
// Sigaction
// Sigprocmask
// Getlogin
// Sigpending
// Sigaltstack
// Ioctl
// Reboot
// Execve
// Vfork
// Sbrk
// Sstk
// Ovadvise
// Mincore
// Setitimer
// Swapon
// Select
// Sigsuspend
// Readv
// Writev
// Nfssvc
// Getfh
// Quotactl
// Mount
// Csops
// Waitid
// Add_profil
// Kdebug_trace
// Sigreturn
// Mmap
// Mlock
// Munlock
// Atsocket
// Kqueue_from_portset_np
// Kqueue_portset
// Getattrlist
// Setattrlist
// Getdirentriesattr
// Searchfs
// Delete
// Copyfile
// Poll
// Watchevent
// Waitevent
// Modwatch
// Getxattr
// Fgetxattr
// Setxattr
// Fsetxattr
// Removexattr
// Fremovexattr
// Listxattr
// Flistxattr
// Fsctl
// Initgroups
// Posix_spawn
// Nfsclnt
// Fhopen
// Minherit
// Semsys
// Msgsys
// Shmsys
// Semctl
// Semget
// Semop
// Msgctl
// Msgget
// Msgsnd
// Msgrcv
// Shmat
// Shmctl
// Shmdt
// Shmget
// Shm_open
// Shm_unlink
// Sem_open
// Sem_close
// Sem_unlink
// Sem_wait
// Sem_trywait
// Sem_post
// Sem_getvalue
// Sem_init
// Sem_destroy
// Open_extended
// Umask_extended
// Stat_extended
// Lstat_extended
// Fstat_extended
// Chmod_extended
// Fchmod_extended
// Access_extended
// Settid
// Gettid
// Setsgroups
// Getsgroups
// Setwgroups
// Getwgroups
// Mkfifo_extended
// Mkdir_extended
// Identitysvc
// Shared_region_check_np
// Shared_region_map_np
// __pthread_mutex_destroy
// __pthread_mutex_init
// __pthread_mutex_lock
// __pthread_mutex_trylock
// __pthread_mutex_unlock
// __pthread_cond_init
// __pthread_cond_destroy
// __pthread_cond_broadcast
// __pthread_cond_signal
// Setsid_with_pid
// __pthread_cond_timedwait
// Aio_fsync
// Aio_return
// Aio_suspend
// Aio_cancel
// Aio_error
// Aio_read
// Aio_write
// Lio_listio
// __pthread_cond_wait
// Iopolicysys
// Mlockall
// Munlockall
// __pthread_kill
// __pthread_sigmask
// __sigwait
// __disable_threadsignal
// __pthread_markcancel
// __pthread_canceled
// __semwait_signal
// Proc_info
// sendfile
// Stat64_extended
// Lstat64_extended
// Fstat64_extended
// __pthread_chdir
// __pthread_fchdir
// Audit
// Auditon
// Getauid
// Setauid
// Getaudit
// Setaudit
// Getaudit_addr
// Setaudit_addr
// Auditctl
// Bsdthread_create
// Bsdthread_terminate
// Stack_snapshot
// Bsdthread_register
// Workq_open
// Workq_ops
// __mac_execve
// __mac_syscall
// __mac_get_file
// __mac_set_file
// __mac_get_link
// __mac_set_link
// __mac_get_proc
// __mac_set_proc
// __mac_get_fd
// __mac_set_fd
// __mac_get_pid
// __mac_get_lcid
// __mac_get_lctx
// __mac_set_lctx
// Setlcid
// Read_nocancel
// Write_nocancel
// Open_nocancel
// Close_nocancel
// Wait4_nocancel
// Recvmsg_nocancel
// Sendmsg_nocancel
// Recvfrom_nocancel
// Accept_nocancel
// Msync_nocancel
// Fcntl_nocancel
// Select_nocancel
// Fsync_nocancel
// Connect_nocancel
// Sigsuspend_nocancel
// Readv_nocancel
// Writev_nocancel
// Sendto_nocancel
// Pread_nocancel
// Pwrite_nocancel
// Waitid_nocancel
// Poll_nocancel
// Msgsnd_nocancel
// Msgrcv_nocancel
// Sem_wait_nocancel
// Aio_suspend_nocancel
// __sigwait_nocancel
// __semwait_signal_nocancel
// __mac_mount
// __mac_get_mount
// __mac_getfsstat